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SAKYO KANDA. 



in some cases and irregular in others. The figures given are, 

 therefore, somewhat arbitrary. To avoid this inaccuracy, a 

 few typical examples of movement are shown in figures as follows: 



FIG. 2. 



The arrows in the figure indicate the movements during the 

 experiment, and the dots the movements of the animals after 

 being placed on the plate but before the commencement of the 

 experiment, i. e., before the plate was covered by the dark box. 



One thing is clear. Some of the animals on the dry glass 

 plate and also those placed on a dry wooden plate, in an experi- 

 ment the results of which will be seen shortly after this, oriented 

 themselves and crawled downward, in spite of the mechanical 

 difficulties due to their shells. 



Experiment C. In the next series, a dry wooden plate was used 

 instead of the dry glass plate, in the same manner as in the above 

 experiment. Of 60 animals used 24 dropped off, 19 or 52 per 

 cent, of the remainder oriented and crawled downward, 6 or 

 16 per cent, crawled up and 4 crawled horizontally. Positive 

 instead of negative geotropism was dominant, even though 

 the experiments were conducted at the angle of 90. 



Experiment D. The following series was of the same nature, 

 except that the animals were placed with their heads down, and 

 the time of experimentation was limited to one minute. Of 60 

 individuals used 33 dropped, 21 or 77 per cent, of those remaining 



